Role of Viscoelastometric Testing in the Development and Validation of a Clinical-biological Score for Predicting Bleeding in Patients With Malignant Haematological Disorders and Severe Thrombocytopenia (VISCOTHEM-2)

The patients included will be selected from the entire cohort of patients with haematological malignancies:

• those admitted to the haematology day unit for treatment or assessment,
• or patients admitted to the haematology inpatient ward,
• or patients being monitored in the haematology outpatient clinic.

Inclusion Criteria:

• Adult patients;
• Who have been informed about the study and have freely given their informed consent to participate in the study;
• With a malignant haematological disorder or bone marrow failure, whether treated or untreated and at any stage of treatment;
• With central thrombocytopenia strictly below 20 G/L in a blood sample taken less than 72 hours ago and not having received a transfusion since;
• Admitted to a haematology day unit or inpatient ward, or being followed up at a haematology outpatient clinic;
• With or without active bleeding;
• Affiliated with or covered by a social security scheme.

Exclusion Criteria:

• Patients who have received at least one of the following treatments:
• Antiplatelet agents within 7 days prior to enrolment,
• Vitamin K antagonists within 7 days prior to enrolment,
• Direct oral anticoagulants within 72 hours prior to enrolment,
• Low molecular weight heparin within 24 hours prior to inclusion,
• Unfractionated heparin within 6 hours prior to inclusion,
• Bruton's tyrosine kinase inhibitor (ibrutinib, zanubrutinib or acalabrutinib) within 72 hours prior to inclusion;
• Patients with a history of thrombopathy;
• Patients with a history of haemostatic disorders carrying a risk of haemorrhage or thrombosis;
• Thrombocytopenia associated with immune thrombocytopenic purpura or disseminated intravascular coagulation;
• Patients already enrolled in the study;
• Pregnant or breastfeeding women;
• Patients under guardianship or curatorship;
• Patients who do not understand French;
• Patients under judicial protection.